Overpopulation and Reactionary Environmentalism
Anxiety about human overpopulation seems to be everywhere in popular culture. It appears in dozens of science fiction novels, some by writers whose work I admire and respect, such as Ursula K. Le Guin’s The Lathe of Heaven. In 1968’s Stand on Zanzibar by John Brunner, set in 2010, a radio presenter states that the human population in the novel – eight billion, the current real-world global population – could fit in rectangles one foot by two feet on the Tanzanian island of Zanzibar (Unguja, one presumes, since Zanzibar consists of two islands).
Jamiroquai’s “Virtual Insanity” laments “Hell, it’s a wonder man can eat at all / When things are big that should be small”, and Gorillaz’ “Stylo” sings of humanity “coming up to the overload”.
Many dystopian films have also been made about the issue of overpopulation. Blade Runner from 1982 is set in an overpopulated and polluted Los Angeles in 2019, perpetually drenched in rain. The bleak 1973 film Soylent Green, based on Harry Harrison’s 1966 novel Make Room! Make Room! is set in the then-future year of 2022, in a world so overpopulated that it is impossible to feed everyone. It ends with the horrifying revelation that, in the absence of enough food, the processed Soylent Green wafers are being made out of euthanised human corpses. (Incidentally, this twist doesn’t appear in the original book. Harry Harrison was dismayed by the changes the film made to his vision.) Most recently, the Marvel Cinematic Universe film Avengers: Infinity War explored the issue of overpopulation through its villain, Thanos, whose ultimate plan is to reduce the population of the universe.
And, numerous times over the years, the elder statesman of natural history, David Attenborough, has warned of the dangers human overpopulation poses to the climate, wild animal habitats, and to the natural world, referring to population growth as “the fundamental source of all our problems”. He has said that people in lower-income countries, where fertility rates are higher, should be given education on birth control to fight the scourge of population growth.
Attenborough’s views on human overpopulation are nothing new. In fact, we can trace concerns about population growth, and overpopulation, all the way back to 1798, when Thomas Malthus published An Essay on the Principle of Population. Malthus argued that, as food becomes more abundant, humans tend towards population growth, rather than maintaining a higher standard of living. It was this tendency, Malthus believed, that created poverty and want. War, famine, and disease, therefore, all help to keep the balance in check, and are, in the Malthusian view, unfortunate necessities.
In 1962, experiments conducted by ethologist John B. Calhoun appeared to validate Malthus’s concerns. The details of these experiments were published as the article “Population Density and Social Pathology” in Scientific American. In the article, Calhoun describes two experiments he had conducted on 32 rats, and then again on 56 rats. The rats were placed in large, free-range enclosures with ramps and separate living spaces, and given protection from predators and disease, as well as unlimited access to food and water. This enabled unfettered population growth, as Malthus described it, with the population in both experiments booming to 80 rats.
Calhoun’s “rat utopia” descended into a vision of the apocalypse: Female rats began to suffer miscarriages, stillbirths and deaths in childbirth. Those who did give birth failed to mother their children and even abandoned them. The males experienced “behavior disturbances”, ranging from “sexual deviation to cannibalism and from frenetic overactivity to pathological withdrawal from which individuals would emerge to eat, drink and move about only when other members of the community were asleep.” Perhaps most disturbingly, Calhoun noted: “…infant mortality ran as high as 96 percent among the most disoriented groups in the population”.
Calhoun later repeated the experiment with a larger enclosure that could house up to 4,000 mice. The population topped out at 2,200 mice, who also exhibited signs of behavioural disturbance. By the 600th day of the experiment, the enclosure, dubbed “Universe 25” by Calhoun, had reached the point of extinction. The mice had developed such poor social skills they were unable to reproduce.
Calhoun called these overcrowded enclosures “behavioral sinks”, and believed that the experiments foreshadowed what may become of humanity, should we continue to reproduce in unsustainable numbers.
In 1962, it was the tail end of the baby boom following the devastation of the Second World War. This article shocked America, and shocked the world. It continues to shock and terrify the lay reader, because its implications for humanity are clear: We live in a time of abundant food and clean water, and low chance of dying from infectious disease or predators. We pack ourselves into dense cities. Clearly, we are on the road to societal collapse within a few short generations.
At least, that is what Paul Ehrlich argued in his 1968 book The Population Bomb, whose cover bore the stark warning: “WHILE YOU ARE READING THESE WORDS FOUR PEOPLE WILL HAVE DIED FROM STARVATION. MOST OF THEM CHILDREN.” Ehrlich proposed that worldwide famine was inevitable with the growth in population. When these predicted famines failed to materialise, Ehrlich remained convinced, arguing in 2009 that his book had been “too optimistic” about humanity’s future.
Overpopulation remains a concern today, particularly in the face of the biggest concerns of our time: Climate change and a global cost-of-living crisis, which many attribute to excessive strain on the Earth’s resources. Often, human population growth is likened to a cancer, where there are too many of us, multiplying rapidly, taking up the Earth’s resources.
So, is it actually true? Is human population to blame for our woes? And should we, as Attenborough has suggested, implement systems of population control to incentivise having fewer children?
In his 1988 essay “The Population Myth”, the social theorist Murray Bookchin decries Malthusianism and its descendants in very strong terms. He dubs Thomas Malthus a “craven English parson” whose theory was “an unfeeling justification for the inhuman miseries inflicted on the mass of English people by land grabbing aristocrats and exploitative ‘industrialists.’” Bookchin notes that, by the 1920s, “Malthusianism acquired an explicitly racist character”, in which population control was used an excuse for maintaining racial purity in the United States. He also notes that the Nazis justified their extermination of six million Jewish people in the Holocaust by using Malthusian arguments.
Bookchin was a strong environmentalist, and he did not deny the impact of human activities on the environment. However, his essay states that “Divested of its social core, ecology can easily become a cruel discipline”. He criticises Ehrlich in the same strong terms as Malthus, as a misanthrope. He points out that Ehrlich’s bestseller advocated a U.S. government agency which would take “whatever steps are necessary” to reduce human population.
If not overpopulation, then, to what did Bookchin attribute environmental harms? Put simply, Bookchin blamed capitalism. In his book The Next Revolution, Bookchin argued that “By the very logic of its grow-or-die imperative, capitalism may well be producing ecological crises which gravely imperil the integrity of life on this planet.”
For Bookchin, to argue that overpopulation is the issue is to miss the forest for the trees. The poverty, environmental degradation, famine and war associated with overpopulation is not, in Bookchin’s view, down to humanity’s selfish drive to keep having babies. It is down to capitalism, a system which requires endless, unsustainable growth and overconsumption of finite resources for the sake of enriching a few, an economy of endless growth rather than a steady state. In the same work, Bookchin warns that these issues cannot be “cured piecemeal, but must be solved by sweeping changes in the often hidden sources of crisis and suffering”.
Very well, that is one theorist’s opinion. But what does the data say?
Well, it doesn’t look good for the Malthusians, let’s put it that way.
In 2024, data scientist Hannah Ritchie debunked overpopulation in a video for Big Think, titled “The myth of overpopulation”. First, she points out, the assumption of Malthusians like Ehrlich is that population growth would be exponential.
We now know, of course, that the baby boom came to a halt in the 1970s. While the population has continued to grow, it has continued at a slower rate. Growth rates actually peaked in 1963 – half a decade before Ehrlich’s book came out. By 2021, this rate had halved, according to a 2022 review by the United Nations on world population prospects.
In fact, the UN suggests that the global death rate will outpace the global birth rate by 2080, albeit with some rather large uncertainty. Nevertheless, the UN’s prediction is that “there is about a 50 per cent chance that the world’s population will peak—that its size will stabilize or begin to decrease—before 2100”. A 2024 study by the UN has found that 63 countries around the world have already hit their peak for population growth, including very populous countries like China, Germany, Japan and the Russian Federation.
Ritchie points out that what the Malthusians underestimated was the fall in global fertility rates – that is, the number of children being born, rather than whether or not people can have children. People in wealthier countries are having fewer children, with an average of 2.3 children per birthing parent globally in 2022. This makes sense when you consider that for much of human history, there was a good reason to have more children, as more children meant firstly more hunters and gatherers for your group; then more hands to work on your subsistence farm; then more children to put to work contributing to the household income. In countries where household incomes are higher and access to basic necessities is easier, people tend to have fewer children.
On top of this, advancements in agriculture have staved off Ehrlich’s predicted famines. (Indeed, Fritz Haber and Carl Bosch’s discovery of an industrial process for producing ammonia between 1918 and 1931 has enabled the lives of between 3 and 3.5 billion people worldwide.)
In areas where fertility rates are high – such as sub-Saharan Africa, a particular target of Attenborough’s disdain – per-capita CO2 emissions are quite low, compared to the United States, which is one of the world’s biggest polluters and has a fertility rate of just 1.7 per birthing parent. Thus, high fertility rates in the Global South and, more broadly, population growth in general, has no direct link to negative impact on the environment.
To put it another way: The issue is not one of overpopulation. It is one of overconsumption. Namely, it is one where countries around the world which have the highest incomes consume resources at a higher rate than the planet can replenish or mitigate. It is not human lives that are a cancer on the world. It is the system of distributing goods and resources, one which relies on private ownership, endless growth and capital accumulation, that is the cancer killing the Earth.
Many countries around the world – Italy, Germany and Finland, for example – have populations where over one in five people (greater than 22%) are aged over 65. In Japan, this is more than 7 in 25 (29.1%). As fertility rates plummet in higher-income countries, these societies may suffer labour shortages, economic stagnation, collapse in tax revenues, reductions in services, shrinking markets, and, of course, an excess of all the diseases and maladies associated with old age. It is these stark futures that are predicted in science fiction novels such as Brian Aldiss’s Greybeard and P. D. James’s The Children of Men.
It is worth noting that the behavioral sinks described by Calhoun cannot easily be analogised as the Earth. In fact, humans are quite bad at estimating scales like this. Eight billion people sounds like a lot, and it is. But many people would assume this indicates the Earth is full to bursting of people. In actual fact, if every human alive today were thrown into a big pile in the Grand Canyon in Arizona, they wouldn’t fill it up. And it isn’t even close, either. The Grand Canyon has an estimated volume of 4.17 trillion m3, while humans take up an estimated 0.062 m3. Ergo, it would take 67 trillion people to fill the Grand Canyon. And, bear in mind, that number would not even come close to oversaturating the Earth.
It is undeniable that humans are having a significant impact on the environment: the air we breathe, the water we drink, the food we eat, the climate, and wild habitats around the world. But human impacts on the environment do not begin and end with population growth. It is not the “source of all our problems”. Our addiction to economic growth is.
It is not that there are too many people in the world placing excessive demand on the world’s resources. Rather, it is the unsustainable lifestyle that the 17.5 percent (1.4 bn) of the total human population (≈8 bn) who live in high-income countries (those countries with a gross national income of over $14,005 per capita) are living. It is that over 70% of global CO2 emissions can be attributed to just 78 corporate entities.
Of course, those of us fortunate enough to live in high-income countries should not take that last statistic as carte blanche to be as wasteful as we wish. Indeed, the biggest corporate polluters in the world are fossil fuel companies, and much of that pollution is produced through demand for electricity and petroleum-fuelled motor vehicles. We all bear responsibility for this.
It is not overpopulation that will cause famine, but frequent extreme weather events and desertification which put strain on global agriculture, causing food shortages, absolutely will. Right now, voicing concern about overpopulation is rather like rearranging deck chairs on the Titanic.
And yet, overpopulation is the myth that will not die.
The debate around human overpopulation once again came to prominence in 2018, when the Marvel Cinematic Universe film Avengers: Infinity War revealed the antagonist, Thanos’s motivations. Thanos came from a planet which became overpopulated, leading to the extinction of his people. And so, to prevent a Malthusian crisis from happening again, he takes the next logical step and (spoilers for a seven-year-old film) turns half the living beings in the universe to dust by snapping his fingers, thus cutting the universe’s resource consumption in half.
I mean, obviously.
At least some viewers were impressed by Thanos’s motivations, proclaiming that “Thanos Did Nothing Wrong“. One could take this as a joke, but a non-zero percentage of these people were dead serious. I cannot stress enough how bleak and misanthropic this view of other people is. And while Doctor Strange directly accuses Thanos of desiring genocide and murder, the film’s writing and grammar poses Thanos as darkly heroic. His motives are presented as noble and next to impossible to argue against. It’s quite telling that at no point does a character actually argue against Thanos’s views, only his plans. His views on population are not taken by the heroes to be factually incorrect; it is merely what Thanos does about those views that is seen as abhorrent.
From this, one can only assume the film’s screenwriters believed Thanos’s motivations to be sympathetic, logical and even topical in the face of climate change. Which, in my opinion, verges on malpractice when it comes to putting environmentalist messaging in family entertainment.
In 2012, an editorial in the Journal of Sustainable Agriculture noted that at that time, we were already growing enough food for 10 billion people. Today, our food production capacity could feed as many as 16 billion people, based on 2019 estimates. Despite this, up to 733 million people went hungry in 2023. This is not an issue of scarcity and insufficiency. It is one where certain groups of people are seen as more “deserving” of food than others. Moreover, it is one where there is considered to be no incentive to feed everyone, as there’s no money to be made in it.
The cruelty of Malthusian logic is that, in defining the world’s poorest people as reproducing to excess, we create a false narrative that their hunger is some kind of retribution for their excesses; that they are “deserving” of “punishment” for setting the world out of balance. People like David Attenborough, well-meaning as they may be, cast blame for ecological catastrophe on the poorest countries in the world for their high fertility rates. Meanwhile, all the luxuries and comforts they enjoy contribute to CO2 emissions as much as more than threefold.
It is not subsistence farmers in sub-Saharan Africa who are driving the world towards mass extinction. It is us. The richest people in the world. And the people we vote for.
No sooner had Donald Trump taken office on 20 January 2025 that he signed an executive order to withdraw the United States from the Paris Agreement for the second time. And the United Kingdom’s four-times-elected Conservative Party, which ruled from 2010 to 2024, was and remains firmly in the pocket of donors who make much of their money from climate-denying fossil fuel firms. (Not that Labour is any better.)
The myth of “overpopulation” is not just a bad argument. It lays the groundwork for ecofascism. It grants legitimacy to an ontology that sections human lives into those that have value and those that must be eradicated for the common good. It makes excuses for capital gobbling up the earth. It lays the blame for environmental destruction at the feet of people whose environmental impact is negligible, compared to the excessive consumption to which we privileged few have become accustomed.
A world that wants to halt and mitigate the worst of climate disaster – much of which is now inevitable even with action – has to get serious about reducing consumption and building more sustainable economies. And as I watch the billionaire Donald Trump once more enter the White House on a raft of lies and deceit, supported by his wealthy, Hitler-saluting cronies, I do not feel optimistic about that prospect.
Bibliography
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- “David Attenborough: ‘We must control our population’“, BBC News, 2013.
- An Essay on the Principle of Population, Thomas Malthus, 1798.
- “Population Density and Social Pathology”, Scientific American, 1962.
- “The Population Myth”, Murray Bookchin, 1988
- The Next Revolution, Murray Bookchin, 2015.
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- Thanos snaps his fingers – Avengers: Infinity War (2018, dir. Anthony and Joseph Russo)
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The illustration for this essay was photographed by Mike Chai.